Github user mattyb149 commented on a diff in the pull request: https://github.com/apache/nifi/pull/2615#discussion_r209658382 --- Diff: nifi-nar-bundles/nifi-elasticsearch-bundle/nifi-elasticsearch-client-service/src/main/java/org/apache/nifi/elasticsearch/ElasticSearchLookupService.java --- @@ -0,0 +1,255 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +package org.apache.nifi.elasticsearch; + +import com.fasterxml.jackson.databind.ObjectMapper; +import org.apache.nifi.annotation.lifecycle.OnEnabled; +import org.apache.nifi.components.PropertyDescriptor; +import org.apache.nifi.controller.ConfigurationContext; +import org.apache.nifi.expression.ExpressionLanguageScope; +import org.apache.nifi.lookup.LookupFailureException; +import org.apache.nifi.lookup.LookupService; +import org.apache.nifi.processor.util.StandardValidators; +import org.apache.nifi.reporting.InitializationException; +import org.apache.nifi.schema.access.SchemaNotFoundException; +import org.apache.nifi.serialization.SchemaRegistryService; +import org.apache.nifi.serialization.SimpleRecordSchema; +import org.apache.nifi.serialization.record.MapRecord; +import org.apache.nifi.serialization.record.Record; +import org.apache.nifi.serialization.record.RecordField; +import org.apache.nifi.serialization.record.RecordFieldType; +import org.apache.nifi.serialization.record.RecordSchema; +import org.apache.nifi.serialization.record.type.RecordDataType; + +import java.io.IOException; +import java.util.ArrayList; +import java.util.Collections; +import java.util.HashMap; +import java.util.List; +import java.util.Map; +import java.util.Optional; +import java.util.Set; +import java.util.stream.Collectors; + +public class ElasticSearchLookupService extends SchemaRegistryService implements LookupService { + public static final PropertyDescriptor CLIENT_SERVICE = new PropertyDescriptor.Builder() + .name("el-rest-client-service") + .displayName("Client Service") + .description("An ElasticSearch client service to use for running queries.") + .identifiesControllerService(ElasticSearchClientService.class) + .required(true) + .build(); + public static final PropertyDescriptor INDEX = new PropertyDescriptor.Builder() + .name("el-lookup-index") + .displayName("Index") + .description("The name of the index to read from") + .required(true) + .expressionLanguageSupported(ExpressionLanguageScope.VARIABLE_REGISTRY) + .addValidator(StandardValidators.NON_EMPTY_VALIDATOR) + .build(); + + public static final PropertyDescriptor TYPE = new PropertyDescriptor.Builder() + .name("el-lookup-type") + .displayName("Type") + .description("The type of this document (used by Elasticsearch for indexing and searching)") + .required(false) + .expressionLanguageSupported(ExpressionLanguageScope.VARIABLE_REGISTRY) + .addValidator(StandardValidators.NON_EMPTY_VALIDATOR) + .build(); + + private ElasticSearchClientService clientService; + + private String index; + private String type; + private ObjectMapper mapper; + + @OnEnabled + public void onEnabled(final ConfigurationContext context) throws InitializationException { + clientService = context.getProperty(CLIENT_SERVICE).asControllerService(ElasticSearchClientService.class); + index = context.getProperty(INDEX).evaluateAttributeExpressions().getValue(); + type = context.getProperty(TYPE).evaluateAttributeExpressions().getValue(); + mapper = new ObjectMapper(); + } + + @Override + protected List<PropertyDescriptor> getSupportedPropertyDescriptors() { + List<PropertyDescriptor> _desc = new ArrayList<>(); --- End diff -- Just a style nitpick, these can be set up in the constructor or a static block (I think the former is preferred?). Unless they're dynamic the list only needs to be created once, where this method gets called often IIRC.
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